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A fast directional continuous spherical wavelet transform

J. D. McEwen·M. P. Hobson·A. N. Lasenby·D. J. Mortlock
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Abstract

A fast algorithm for Antoine and Vandergheynst's (1998) directional continuous spherical wavelet transform (CSWT) is presented. Computational requirements are reduced by a factor of O(\sqrt{N}), when N is the number of pixels on the sphere. The spherical Mexican hat wavelet Gaussianity analysis of the WMAP 1-year data performed by Vielva et al. (2003) is reproduced and confirmed using the fast CSWT. The proposed extension to directional analysis is inherently afforded by the fast CSWT algorithm.

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J. D. McEwen, M. P. Hobson, A. N. Lasenby, D. J. Mortlock. 2004-09-13. A fast directional continuous spherical wavelet transform. https://arxiv.org/abs/astro-ph/0409288

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